Apparatus for screening paper stock



A. J. BRooKovER APPARATUS FOR SCREENING PAPER STOCK Nov. 26, 1929.

Filed Oct. 5. 1928 INVENTOR wmho' -r 71K.

A T T ORNE Y5 Patented Nov. 26, 19 2s i ETE l ANDREW J. BROOKOVER, OF DOWNINGTOWN, EENNSYLVANIA APPARATUS FOR. SCREENING PAEES, STOCK Application'filed October 3, 1928. Serial No. 309,957.

This invention relates to apparatus for or less diaphragms than this maybe proscreening paper stock and relates more parvided. ticularly to the driving arrangement for the In the screening of paper-pulp stock the diaphragms of a series of screen boxes. stock is supplied ina fluid state to the stock 5 One object of the invention is the provision receiver 13 and the stock is sifted or screened 55 of a screen-box arrangement embodying a by -the screens 12, this screening action being series of screen boxes, and each screen box assisted and induced by the vibratory diahaving a number of flexible vibratory diaphragms 14 which create a rapid movement phragmswhich are so driven from a series of of the material through the screen spaces shafts that each shaft operates a diaphragm and prevent the clogging of the screen. The 69 of each screen box. 7 screened material flows out of a suitable out- Another object of the invention is the prolet Opening at one side of each of-the secvision of a series of screen boxes arranged in tions of the screen box into a trough or rethis manner, each screen box having a numceiver 20. Movement of the unscreened inaher of flexible diaphragms arranged in the terial which is placed in the stock receiver 5 1; screen box transversely of the series of boxes, 13 is effected longitudinally of the screen box with the operating shafts for the diaphragms by the usual blade or paddle carried by a extending throughout the entire length of the Shaft 21 and driven in any suitable manner, series and operated by individual belt drives A n mber of vscreen boxes or machines, or th lik similar to the box 10, are arranged in a se- Other objects and advantages of the invenrles as shown in Figs. 1 and 2. In the screention will be apparent from the following deg 0f q n es f paper S ock it is usually i ti d f th a o anying drawnecessary to provide a number of different h i whi h screening machines, all operating on the 25 Fig. 1 is a top plan view of a series of paper stock to screen suflicient materialfor screen boxes embodying the present invert the paper-making machine. Thesescreention; ing machines as shown in Fig. 2 are prefer Fi 2 i a id 1 ti f th Series f ably arranged at successively lowerlevels so screen boxes; and that the unscreened material from the dif- I 0 Fig. 3 is a section on the line 3-3 of Fig. ferent boxes is collected in a common longico 1 thr h o f th s r n b x s, tudinally extending fluid conductor, not

Referring more particularlyto the drawshown, and led to the last box in the series, j b reference numerals 10 i di t a termed a rescreening box and indicated 30. screen box adapted for the screening of AS ShOWIl 111 i g h g eight 5 paper-pulp t l; a d th lik Thi Screen screen boxes in the series, indicatedlO, 24, 5

box embodies a, number of screens 12 31- 25, 26, 27, 28, 29 and 30, although Of COUISQ ranged below the top of a pulp-stock receiver hls num y y qulte considerably 13 common t th vari s Screens f th h pendent upon the total machine capacity de- Below the screens are a series of flexible diao phmgms 14 whi h r la d t th i edges It has heretofore been the practice to drive so b means f Clamp b ard 15 whi h thus the cams, knockers or eccentrics connected to divide the screen box into sections, each secthe various flexible diaphragms with a shaft tion including one or more flexible dine extending longitudinally of a screen box phragrns. Each of the flexible diaphragms Operating all the diaphragms on this incliis attached to a block 16 which is fixed at vidual screen, so that, should the power or the top of a rod 17 the lower end of which drive become ineffective on this one shaft is provided with an eccentric or cam follower this entire screen would be out of operation. operated by a shaft, such as the shaft 34:. Or where'a number of screens are driven by As shown, the screen box embodies five secone shaft with all the diaphragms of each 5O tions or diaphragms although of course more screen operated by this one shaft, in case of 109 failure of the power at this one point all the screens will be out of operation. Should a mechanical part of the vibrating devices become effective and require the power to be taken off for repair then all the screens are rendered ineffective. In accordance with the presentinvention however the screen-box diaphragms are driven as follows:

Arranged longitudinally of the series of screen boxes are drive shafts 33, 3 35,36 and 37, these shafts extending the full length of the series, and each shaft being preferably centrally located below one of the flexible diaphragms of a screen box. Thus the shaft 33 extends below the end diaphragm of each of the various screen boxes in the series. Each shaft thus operates one of the flexible diaphragms of each of the various screen boxes so that in case any one of the shafts is stationary, the practical operation of the series of machines is not interrupted, and none of the screen boxes overflows due to the fact that the other screens of the screen boxes are not affected and all continue in their effective operation. As shown the shafts are made up of coupled sections.

The ends of the various shafts 33 to 37 preferably project beyond the ends of'the series, and are independently driven by suitable means, suca as the driving belts 38 which are operated in any suitable-manner.

. As the various bolts 38 are independent of one another the diaphragm-operating shafts are independently driven and a series slipping of one of the beltson its driven belt pulley or the breaking or disconnection of a belt affects equally a diaphragm in each of the various screen boxes in the series. Furthermore where, as shown, the number of screen boxes arranged in the series exceeds the number of diaphragms provided in each screen box fewer driving shafts need be employed, and the arrangement is such that the individual power drives for the various shafts may be readily effected in a more desirable manner; from power shafting usually available at one side of such'a series of machines.

. As the shafting on the screens may run parscreen means allel to the usual constant drive shaft of the paper machine, the necessity of greater twist belts or bevel gears is eliminated.

While the form of apparatus herein described constitutes a preferred embodiment ing each diaphragm, and means for operating said devices comprising a series of shafts, each shaft arranged to extend across the series of boxes from one end to the other of the series, and means on each shaft for operating a device of each box.

2. Apparatus for screening paper stock comprising a series of screen boxes, each box having a plurality of flexible diaphragms arranged laterally of the series of boxes, screen means associated, with said diaphragms in said boxes, a device for vibrating each diaphragm, and means for operating said devices comprising a series of shafts, each shaft being arranged below the entire series of boxes and in parallel arrangement with each other, and means on each shaft for operating a device of each box.

8.- Apparatus for screening paper stock comprising a series of screen boxes, each box having several flexible diaphragms arranged laterally of the series of screen boxes, the number of screen boxes exceeding the number of flexible diaphragms in each box, screen means associated with said diaphragms and said boxes, a device for vibrating each diaphragm, and means for operating said de- Vi-3"S comprising a seriesof shafts, each shaft a1 anged to extend below the series of boxes from one .end to the other of the series and parallel with the other shafts, independent drive belts for each of said shafts, and means on each shaft for operating a device of each box. 1 V

In testimony whereof I hereto :afiix my signature.

ANDREW 'BRooKovER.

CERTIFICATE OF CORRECTION.

Patent No. 1,737,296. Granted November 26, 1929, to

ANDREW J. BROOKOVER.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, line 4, for the word "effective" read "defective"; same page, line 34, for the word "series" read "serious"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 31st day of December, A. D. 1929.

M. J. Moore, (Seal) Acting Commissioner of Patents. 

